Skip fire internal combustion engine control

Abstract

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In one aspect, the working chamber firing that are selected to deliver the desired engine output are determined at least in part based on torque feedback. The torque feedback may be an indication of the torque output of the engine or the torque experienced at some other location in the drive train. In some embodiments, the torque feedback signal is filtered to remove high frequency components of the torque feedback signal in order to help stabilize the system. In another aspect, other operational parameters are used as feedback in the determination of the firing sequence. In yet another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority of Provisional Application No. 61 / 418,779 filed Dec. 1, 2010. This application is also a Continuation-in-part of U.S. application Ser. No. 13 / 101,042 filed May 4, 2011, Ser. No. 13 / 004,839 filed Jan. 11, 2011 and Ser. No. 13 / 004,844 filed Jan. 11, 2011, each of which are Continuations-in-Part of U.S. patent application Ser. No. 12 / 501,345 filed Jul. 10, 2009, which is a Continuation-in-Part of U.S. patent application Ser. No. 12 / 355,725 filed Jan. 16, 2009 which claims the priority of U.S. Provisional Patent Application Nos. 61 / 080,192, filed Jul. 11, 2008; and 61 / 104,222, filed Oct. 9, 2008. U.S. application Ser. Nos. 13 / 004,839 and 13 / 004,844 also claim priority of Provisional Application No. 61 / 294,077 filed Jan. 11, 2010. Each of these priority applications are incorporated herein by reference.FIELD OF THE INVENTION[0002]The present invention relates generally to skip fire control of internal combustio...

AI Technical Summary

Benefits of technology

[0008]In some embodiments, the controller used to determine the firing sequence includes a control block arranged to receive an input signal indicative of a desired output and to generate a firing sequence that delivers the desired output. The control block also receives a torque feedback signal that is indicative of the actual torque output of the engine and determines that firings based at least in part on the torque feedback signal. The torque feedback signal may be filtered to remove high frequency components to help stabilize the system.

Problems solved by technology

Although the concept of skip fire engine control has been around for many years, and its benefits are understood, skip fire engine control has not yet achieved significant commercial success in part due to the challenges it presents.

In many applications such as automotive applications, one of the most significant challenges presented by skip fire engine control is vibration control.

The inability to satisfactorily address vibration concerns is believed to be one of the primary obstacles that has prevented widespread adoption of skip fire.

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